Accumulator device



April 21, 1970 ISAO suwA 3,507,454

ACCUMULATOR DEVICE Filed Feb. 23. 1968 FIG. I 31 O I 19 o L o i 6 o 7' 29/ o o Lo United States Patent 3,507,454 ACCUMULATOR DEVICE Isao Suwa, Tokyo, Japan, assignor to Aoi Seiki Company Limited, Tokyo, Japan, a corporation of Japan Filed Feb. 23, 1968, Ser. No. 707,614 Int. Cl. B6511 75/00; B66c 13/10 US. Cl. 24254 4 Claims ABSTRACT OF THE DISCLOSURE An accumulator device for controlling tension in wires, cables and similar elongated members comprises a pair of spaced apart discs, two series of rotatable wheels carried between the discs having grooves in their peripheral surfaces, the wheels being positioned so the grooves of the first series form a first spiral and the grooves of the second series form a separate second spiral, a first traverser that moves parallel to the Wheel axes at one side of the accumulator, a second traverser similarly arranged at the other side. In use, the wire or other elongated member passes, in series, through the first traverser, the first and second series of wheels and then out the accumulator through the second traverser.

This invention relates to an accumulator device useful for controlling the tension of various elongated flexible members, preventing the loosening of the electric power cables of a crane caused from the moving thereof or accumulating and paying off the travelling elongated members in accordance with its operating conditions.

In wrapping an insulator tape on a bare conductor wire, the wire must travel from one bobbin or reel to another at a constant tension. The tension of the wire, in prior known procedures, is controlled by a pulley assembly adapted to operate separately from the winding machine. A usual pulley assembly comprises a plurality of fixed pulleys spaced apart from each other, a plurality of movable pulleys disposed below the fixed pulleys and weight members hung down from the movable pulleys. The wire is stretched in order between the fixed pulleys and movable pulleys. When a variation of tension occurs in the travelling wire, it is absorbed by movement of the movable pulleys.

However, since the amount of the wire accumulated is relatively small, it is difficult to absorb the large amount of variations in tension. A more important disadvantage in such pulley mechanisms is that the wire is subjected to high friction between the wire and the pulleys, resulting in undesirable curves and fatigue in the wire.

On the other hand, when the pulley assembly is used together with a winding machine, it is required that the assembly has essentially a large accumulating ability, since a wire member, for example an insulated wire, is necessarily accumulated in the pulley assembly when taking off of the wire is interrupted due to various reasons, for instance, changing of bobbins. The prior art accumulators, such as the pulley assembly mentioned above, have a small accumulating ability, so that the travelling of the wire fed from the feeding process is often stopped at the time of changing of a bobbin. The interruption of the travelling of the wire naturally results in lowering of the production efiiciency.

This invention provides a novel accumulator device for accumulating a travelling elongated flexible member at a constant tension comprising at least two discs spaced apart from each other, a driving source in driving connection with the discs to rotate them, two series of rotatable wheels disposed between the discs, the wheels having 3,507,454 Patented Apr. 21, 1970 a plurality of grooves parallel to each other on the peripheral surfaces thereof, the first series of which is positioned so that the grooves thereof are arranged on a first spiral, and the second series of which is positioned so that the grooves thereof are arranged on a second spiral having a direction different from that of the first spiral, a first traverser means movable in the direction parallel to the axes of said wheels and in the range of the length of the first series of said wheels corresponding to the movement of the grooves, a second traverser means movable in the direction parallel to the axes of said wheels and in the range of the length of the second series of said wheels corresponding to the movement of the grooves, whereby the elongated member is passed through the first traverser means, the first and second series of said wheels and the second traverser means.

An elongated member to be accumulated, in the accumulator device according to this invention, is accumulated in the spiral grooves of the Wheels, so that it will travel with a smaller friction. Moreover, since the novel device can possess a relatively large accumulating ability, the device may be advantageously used for various applications.

In the drawings:

FIG. 1 is a plan view of the accumulator device according to this invention;

FIG. 2 is a side elevation of the device illustrated in FIG. 1;

FIG. 3 is a longitudinal section of a part of the device illustrated in FIGS. 1 and 2;

FIG. 4 is a partial perspective view of a guide wheel used in another embodiment of this invention; and

FIG. 5 is a main wheel used in a further embodiment according to this invention.

Referring now to the accompanying drawings, more particularly to FIGS. 1 to 3, the reference numeral 1 shows a main shaft which is pivotally supported on a pedestal A and connected to a driving source stated below. Near the ends of the shaft 1 are secured a pair of circular discs 2. A plurality of axles 3 are disposed between the discs 2 in an annular arrangement. Also said shaft '1 has a support member 4 on the central part thereof.

Two series of guide wheels 5 and 6, such as grooved pulleys, are rotatably supported on said axles 3. The first series of the guide wheels 5 which is positioned nearer to one of the disc 2 are arranged spirally in one direction, likewise the second series of wheels 6 nearer to the other disc 2 is arranged spirally in the other direction.

The support 4 has a pair of main wheels 7, 8 at its opposite ends. These guide wheels and main wheels are provided for leading a travelling wire. The shaft 1 has a penetrating hole 9 to pass the wire therethrough at its central portion.

To one end of the shaft 1 is secured a sprocket 10', connected to another sprocket 12 by a driving chain 13. The sprocket 12 is secured to the driving shaft 11 of a reduction gear which is driven by a driving source 14 such as an electric torque motor 14.

On the pedestal A a pair of screwed or threaded shafts 15 and 16 are rotatably supported parallel to the shaft 1. The threads 17 formed on the shaft 15 have a pitch opposite to the threads 18 of the other shaft 16. The shafts have sprockets 19, respectively, each of which is connected to sprockets 10 secured to each end of the shaft 1 by a driving chain 20 to revolve the threaded shafts 15, 16.

As best shown in FIG. 1, a pair of traverser means 21 and 22 are located on the threaded shafts 15, 16, respectively, which can travel along the shafts in accordance with the revolution thereof. The first traverser means 21 has a traverser body 23 which is provided with a threaded hole intermeshing with the threads of the shaft 15. The traverser means further comprises a pair of vertical supports 24 slightly spaced apart from each other, a pair of side pins 25 extending downward from each of the supports 24, and a check member (not shown) to check a wire extending to the first series of the guide wheels 5. Also an upper check roller 27 is disposed betwen the supports 24 at their upper end portions and a lower check roller 28 is disposed on the traverser body 23. Further a pair of wheels 29 are pivotally carried on each pair of the side pins 25 and contact a pair of rails 30 which are disposed on the pedestal A, thereby preventing rotation of the traverser means 21 and 22 about the threaded Shafts 15 or 16 respectively. On the upper surface of the traverser body 23 is planted a pair of traverser rollers 31 arranged parallel to each other.

In operation, when the accumulator device according to this invention is used for the production or treatment of a line of wire 32, the wire from the wire supply means (not shown) is introduced through traverser rollers 31 and check rollers 27 and 28, and stretched between main wheels 7 and 8. From the main wheel 8 the wire is led to a winding mechanism (not shown) through the traverser means 22. On the other hand the torque mo tor 14 is connected to an electric controlling means (not shown) to control the revolution of the torque motor so as to maintain the tension of the wire.

When the tension applied to the wire is reduced, the shaft 1 is revolved by the torque motor 14 which is energised by the electric power from the controlling device until the tension becomes constant. By the revolution of the shaft 1 the wire is wound on the guide wheels and 6. At this time the threaded shafts and 16 are also revolved since they are connected to the shaft 1 through the sprockets and chains, whereby the traverser means 21 and 22 are moved in opposite direction to each other. Accordingly the wire is found pirally on the two series of the guide wheels 5 and 6 at its inlet and outlet side.

When the tension applied to the wire reaches a predetermined value, the torque motor will stop. The wire, in this condition, travels through the traverser means 21, the first series of the guide wheels 5, main wheels 7 and 8, the second series of the guide wheels 6 and the outlet side traverser means 22. The resistance offered to the passage of the wire through the accumulator is substantially equal to the friction caused by revolution of the wheels, and it is relatively small.

When the tension of the wire is increased for some reason, for example, increasing of the takeup speed of the wire, the change of tension is detected by the torque motor 14, then the main shaft 1 is revolved in the direction such that the wire wound on the guide wheels is taken off until the increased tension is relieved. The tension applied to the wire, therefore, will be maintained at a predetermined constant value.

In practical operation, it is preferred to wind the wire in advance at a suitable length on the guide wheels in order to deal with any variations of the tension.

The accumulator device mentioned above can accumulate a relatively large amount of wire, so that it is not required that the fed wire is in general interrupted in its travel.

In FIG. 4, there is illustrated another embodiment of the accumulator device according to this invention. The modified accumulator is similar to the accumulator device shown in FIGS. 1 to 3 except that the two series of the guide wheels are substituted by a pair of grooved rollers 105 and 106 on each axle 3, each roller having a plurality of annular grooves 109 parallel to each other.

Another modification of the accumulator of this invention is illustrated in FIG. 5, in which a pair of circular rotating discs 107 and 108 are disposed rotatably to said support 4. The rotating discs are provided round their circumferences with a plurality of rotatable guide wheels 110. In this modification, the wire member 32 is led on to the periphery of the guide wheels 107, 108 through the hole 9 bored in the main shaft 1, so that the wire will travel with a reduced resistance. Also in the embodiment mentioned above the guide wheels 5, 6 or guide rollers 105, 106 may be disposed securely on the axles 3. It is required that, in this case, the axles 3 are divided at their central portion and rotatably installed to the discs 2 in order to permit the rotating of the guide wheels or rollers freely, whereby the halves of the axles can rotate independently of each other.

If the distance between the inner end rollers of two series of guide wheels is small, the main wheel and support member may be omitted,

The driving means to drive the shaft 1 is not restricted to torque motors. If desired, a usual electric motor or coiled spring assembly may be used. If a usual electric motor is used, it is required to equip a tension detecting means and controlling means which can control the revolution speed of the main shaft 1. Conversely, when a coiled spring assembly is used as a driving means, such accumulator is suitable for the application to cranes to prevent the loosening of the electric cable thereof.

The accumulator device may be used to accumulate various elongated members, such as electric power cables, strands for rope manufacture, ropes and spun yarns. In such applications, the accumulator will suit for tension controlling. When the accumulator is equipped to a rotating cradle so as to be rotated in its longitudinal direction to the main shaft, it can be used for wire twisting.

What is claimed is:

1. An accumulator device for accumulating a travelling elongated flexible member in its travel between separated points which comprises a pair of discs spaced apart from each other and rotatable about a main axis, a driving source in driving connection with said discs to rotate them about said main axis, a first and second series of rotatable wheels disposed between said discs, the wheels of each of said series being evenly spaced from each other about the periphery of said discs, said wheels having a plurality of grooves on their peripheral surfaces, said grooves being staggered relative to each other in a progressive manner whereby a line running through the grooves of the first series of wheels will describe a first spiral about the periphery of said discs and a line running through the grooves of the second series of wheels will describe a second spiral having a direction different from that of said first spiral, a first traverser means movable in a direction parallel to the axes of said wheels and in the range of the length of said first series of wheels, at second traverser means movable in the direction parallel to the axes of said wheels in the range of the length of said second series of wheels whereby an elongated member in being tension controlled by the accumulator passes in turn through said first traverser means, the first series of wheels, the second series of wheels and said second traverser means.

2. An accumulator device as claimed in claim 1 wherein each of said wheels is a plurality of pulleys each having at least one groove in its peripheral surface.

3. An accumulator device as claimed in claim 1 which further comprises a pair of main wheels rotata'bly arranged to revolve about an axis concentric with said main axis between said first and second series of wheels to receive an elongated member traversing the accumulator between said first and second traverser means, said main wheels leading the elongated member from said first traverser means to said first series of wheels and from said second series of wheels to said second traverser means upon rotation of said discs by said driving source.

4. A device as claimed in claim 3 wherein each of said main Wheels comprise a plurality of pulleys rotatably mounted in a circular arrangement.

References Cited UNITED STATES PATENTS 6 Harris 24254 XR Knights 24254 XR La Tour 24255 Prusak et al. 24255 5 STANLEY N. GILREATH, Primary Examiner W. H. SCHROEDER, Assistant Examiner 

